Auto-balancing device with longitudinally disposed and movable platform sections

ABSTRACT

An auto-balancing transportation device configured for being ridden in a foot forward or sideways standing position. The rider platform has front and rear foot platform areas and two connecting members, located on opposite lateral sides of the device, that couple the front and rear platform areas. Two drive wheels are located under or through the platform. The front and/or rear platform areas are movable or twistable so as to alter the fore-aft tilt of one or more of the connecting members. Position sensors associated with each connecting member are used to drive a corresponding drive wheel. In this manner, differences in fore-aft tilt angle of the two connecting members achieves a turning of the device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/790,301, filed Jan. 9, 2019, entitled Self-Balancing PersonalVehicles, and having Ywanne Ying Chen as inventor.

BACKGROUND OF THE INVENTION

The prior art includes several auto-balancing transport devices. Theseinclude the Segway, developed by Kamen et al and disclosed in U.S. Pat.No. 6,302,230 (among others), the Solowheel, by Chen (U.S. Pat. No.8,807,250) and Hovertrax, also by Chen (U.S. Pat. No. 8,738,278). Theprior art also includes the Hovershoe, disclosed in U.S. patentapplication Ser. No. 15/338,387. These three patents and the Hovershoeapplication are hereby incorporated by reference as though disclosed intheir entirety herein.

The above patents disclose devices that are typically ridden with arider standing facing forward, hips towards the line of direction oftravel. In a conventional skateboard, however, a rider stands sideways.For people who experienced skateboard riding as a child, it might beeasier to learn to ride an auto-balancing device standing sideways thanhips forward.

U.S. Pat. No. 9,101,817, issued to Doerksen, for a Self-StabilizingSkateboard, discloses an auto-balancing device that may be ridden whilestanding sideways. This device (and others like it) is disadvantageousin several aspects. One is that it is difficult to turn. There is asingular wide, flat wheel, and this wheel structure makes turning veryslow or gradual. Other disadvantageous aspects include that the exposedwheel is dangerous, throws rain water, and restricts foot movement.

A need thus exists for an auto-balancing transportation device thatallows a rider to stand sideways yet affords sharper and more responsiveturning.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcome theshortcomings of the prior art.

It is another object of the present invention to provide anauto-balancing transportation device that affords skateboard styleriding (i.e., one foot forward) and more responsive turning.

It is also an object of the present invention to provide such a devicewith two platform sections or components that are movable with respectto one another and that each control a drive wheel, the differentialdriving of the wheels achieving turning.

These and related objects of the present invention are achieved by useof an auto-balancing device with longitudinally disposed and movableplatform sections as described herein.

The attainment of the foregoing and related advantages and features ofthe invention should be more readily apparent to those skilled in theart, after review of the following more detailed description of theinvention taken together with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-2 are bottom and top perspective views, respectively, of oneembodiment of a transportation device in accordance with the presentinvention.

FIGS. 3-4 illustrate another embodiment of an auto-balancing device witha longitudinally disposed platform 115 in accordance with the presentinvention.

FIGS. 5-6 illustrate yet another embodiment of an auto-balancing devicewith a longitudinally disposed platform in accordance with the presentinvention.

FIG. 7 is a perspective view of another embodiment of an auto-balancingdevice in accordance with the present invention in which the drivewheels extend through the platform.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, bottom and top perspective views of a firstembodiment of a transportation device 10 in accordance with the presentinvention are respectively shown.

Device 10 preferably includes a longitudinally disposed foot platform 15that has two foot platform sections 21,22, one located on each lateralside of the platform. Below each platform section is an auto-balancingfoot platform unit or module (herein “FPU”) 30,50. In FIG. 1, platformsection 21 is coupled to FPU 30 and platform section 22 is coupled toFPU 50.

Each FPU preferably has a drive wheel 31,51 and an associated motor32,52. The motor may be a hub motor or other motor arrangement. Each FPUalso preferably has a control circuit 34,54, a position sensor (such asa fore-aft tilt angle sensor or gyroscopic sensor or other sensor)35,55, and a battery 36,56. Alternatively, the sensor for a given FPUmay be provided with the associated platform section. Regardless, thesensors are preferably configured to sense the fore-aft tilt angle oftheir foot platform section.

FPUs 30,50 are preferably configured such that the control circuitdrives the drive wheel 31,51 towards auto-balancing the FPU based ondata from the sensor 35,55. Auto-balancing arrangements, including thosefor use in an FPU, are known in the art.

FPUs 30,50 are preferably coupled to one another such that the drivewheels have a common axis of rotation, though they may be otherwisearranged without departing from the present invention.

Foot platform sections 21,22 each have a front end A, a rear end B, anda connecting member C therebetween. The end portions may be referred toas subsections, such as 21A,22A in the front and 21B,22B in the rear,and the connecting members as 21C,22C. As shown in FIG. 6, a rider wouldtypically stand with a foot on subsections 21A,22A and the other onsubsections 21B,22B. By switching weight from heel to ball on theirfeet, and vice versa, the rider can change the tilt of the connectingmember 21C,22C relative to one another and thus achieve turning.

For example, if in FIG. 2, connecting member 22C is tilted forward by 1degree and connecting member 21C is tilted forward by 5 degrees, thenthere is a 4 degree differential between the connecting members andwheel 31 is driven faster than wheel 51, turning device 10 to the right.

It should be recognized that which longitudinal end is the front or rearmay be arbitrary as a rider may mount from either direction (though thedevice may be made with a dedicated front and rear).

Note that equal and opposite tilting of the connecting members 21C,22Cwould allow the device to pivot in place, something prior artauto-balancing skateboard devices cannot achieve.

By affording independent, or relative difference based, control of twodrive wheels, the present invention is able to achieve much moreresponsive turning than available in prior art devices. Further, it isachieved in a manner that is intuitive to a rider, which makes learningto ride easier, and increases the potential uses of thedevice—commuting, recreation, games and competitions, etc.

It should also be recognized that in the present invention, the platformhas a greater longitudinal dimension than lateral dimension. This may besimply longer than wide, or 1.5× longer, or 2× longer or 2.5× longerthan wide, or more.

Referring to FIGS. 3-4, another embodiment of an auto-balancing device110 with a longitudinally disposed platform 115 in accordance with thepresent invention is shown.

Device 110 is similar to device 10 and similar components may have thesame reference numerals in the tens and ones digits. One difference isthat while platform 15 of device 10 is two physically separate items,i.e., not directly connected, the two platform sections 121,122 ofplatform 115 are coupled by a flexible membrane 140. The membrane ispreferably coupled to the platform sections in such a way as to give thefeel of one contiguous platform surface yet afford sufficientflexibility such that the platform sections can move in fore-aft tiltrelative to one another. The membrane may be made of latex rubber orflexible plastic or other suitable material.

Similar to device 10, each platform section 121,122 has a frontsubsection 121A,122A, a rear subsection 121B,122B, and a connectingmember 121C,122C therebetween.

FIG. 4 illustrates one potential assembly technique for device 110.Arrow A indicates the platform being mounted to FPUs 130,150. Platform115 may be screwed to the FPUs or otherwise fastened. Couplingtechniques for joining the FPUs are known in the art.

Referring to FIGS. 5 and 6, yet another embodiment of an auto-balancingdevice 210 with a longitudinally disposed platform 215 in accordancewith the present invention is shown.

Device 210 includes a contiguous or one piece platform 215, albeitpreferably with a longitudinally disposed hole 271 in it to enhancetwisting. Platform 215 preferably has subsections 221A,222A up front,subsections 221B,222B in the rear, and connecting members 221C,222Ctherebetween.

FIG. 6 illustrates where a rider might stand. For example, one foot 5 atthe front and one foot 6 at the rear. It can be seen that each foottouches a pair of subsections. As a rider leans forward or rearward (inthe line of direction of travel) the device will go in that direction,however, when a rider twists the platform longitudinally, the connectingmembers 221C,222C will experience different fore-aft tilt angles causingthe device to turn.

Referring to FIG. 7, a perspective view of another embodiment of anauto-balancing device 310 with longitudinally disposed platform inaccordance with the present invention is shown. Device 310 includes aflexible platform 315 with holes therein. Center hole 371 accommodatestwo drive wheels 330,350 that extend above the platform's top surface.Holes 372 are provided at the longitudinal ends (at subsections321A,322A,321B,322B) to facilitate twisting.

Device 310 operates similar to device 210. A rider standing skateboardstyle leans forward or rearward to initiate movement and twists theboard by alternatively applying weight to the balls and heels of his orher feet. This twisting causes connecting members 321C,322C to havedifferent fore-aft tilt angles, as detected by sensors 335,355,respectively, to achieve a turning of the device.

While the invention has been described in connection with specificembodiments thereof, it will be understood that it is capable of furthermodification, and this application is intended to cover any variations,uses, or adaptations of the invention following, in general, theprinciples of the invention and including such departures from thepresent disclosure as come within known or customary practice in the artto which the invention pertains and as may be applied to the essentialfeatures hereinbefore set forth, and as fall within the scope of theinvention and the limits of the appended claims.

1. An auto-balancing transportation device, comprising: a platformhaving first and second front subsections and first and second rearsubsections, and a first connecting member located between the firstfront and rear subsections and a second connecting member locatedbetween the second front and rear subsections; a first wheel, a firstdrive motor, and a first sensor associated with the first connectingmember; a second wheel, a second drive motor, and a second sensorassociated with the second connecting member; a control circuit thatdrives the first drive motor toward auto-balancing the first connectingmember based on data from the first sensor and that drives the seconddrive motor toward auto-balancing the second connecting member based ondata from the second sensor; and wherein the fore-aft tilt angle of thefirst and second connecting members is changeable by a rider during useand a difference in fore-aft tilt angle between the first and secondconnecting members achieves differential driving of the first and secondwheels and a turning of the device.
 2. The device of claim 1, whereinthe platform is greater in longitudinal dimension than lateraldimension.
 3. The device of claim 1, wherein the platform is 1.5 timesor more greater in longitudinal dimension than lateral dimension.
 4. Thedevice of claim 1, wherein the first and second wheels are wholly belowthe platform.
 5. The device of claim 1, wherein the first and secondwheels are in part below the platform and in part above the platform. 6.The device of claim 1, wherein the first sensor senses fore-aft tiltangle of the first connecting member.
 7. The device of claim 1, whereinthe first and second connecting members are substantially parallel toone another, and are physically separate from one another.
 8. The deviceof claim 1, wherein the first and second connecting members are coupledto one another through a flexible coupler.
 9. The device of claim 1,wherein the first and second connecting members are formed in acontiguous board that has an opening defined therein, the board beingsufficiently flexible to allow movement of the first and secondconnecting members relative to one another in fore-aft tilt angle. 10.The device of claim 9, wherein the first and second wheels extend abovethe platform through the opening.
 11. The device of claim 1, wherein thefirst and second front subsections are configured to move relative toone another in fore-aft tilt angle, and movement of the first and secondfront subsections relative to one another in fore-aft tilt angle causesmovement of the first and second connecting members relative to oneanother.
 12. The device of claim 1, wherein the first and second rearsubsections are configured to move relative to one another in fore-afttilt angle, and movement of the first and second rear subsectionsrelative to one another in fore-aft tilt angle causes movement of thefirst and second connecting members relative to one another.
 13. Anauto-balancing transportation device, comprising: a platform havingfirst and second front subsections and first and second rearsubsections, and a first connecting member located between the firstfront and rear subsections and a second connecting member locatedbetween the second front and rear subsections; a first wheel, a firstdrive motor, and a first sensor associated with the first connectingmember; a second wheel, a second drive motor, and a second sensorassociated with the second connecting member; a control circuit thatdrives the first drive motor toward auto-balancing the first connectingmember based on data from the first sensor and that drives the seconddrive motor toward auto-balancing the second connecting member based ondata from the second sensor; and wherein the first connecting member iscapable of fore-aft tilt angle movement while the fore-aft tilt angle ofthe second connecting member is unchanged.
 14. The device of claim 13,wherein the second connecting member is capable of fore-aft tilt anglemovement while the fore-aft tilt angle of the first connecting member isunchanged.
 15. The device of claim 13, wherein the platform is greaterin longitudinal dimension than lateral dimension.
 16. The device ofclaim 13, wherein the first and second wheels are wholly below theplatform.
 17. The device of claim 13, wherein the first and secondwheels are in part below the platform and in part above the platform.18. The device of claim 13, wherein the first and second connectingmembers are formed in a contiguous board that has an opening definedtherein, the board being sufficiently flexible to allow movement of thefirst and second connecting members relative to one another in fore-afttilt angle.
 19. The device of claim 18, wherein the first and secondwheels extend above the platform through the opening.
 20. The device ofclaim 13, having at least one of: the first and second front subsectionsconfigured to move relative to one another in fore-aft tilt angle, andmovement of the first and second front subsections relative to oneanother in fore-aft tilt angle causing movement of the first and secondconnecting members relative to one another; and the first and secondrear subsections configured to move relative to one another in fore-afttilt angle, and movement of the first and second rear subsectionsrelative to one another in fore-aft tilt angle causing movement of thefirst and second connecting members relative to one another.